This reverts commit 22322409ddb527ac855ba71d10dadcb9da415f81.
The reverted commit had at least the following problems:
- It adds a lot of filesystem handling code to an individual VO.
- The added code is duplicated from vo_jpeg.c.
- The added code has exit_player() calls. A VO should not exit the
whole program. Even if vo_jpeg still has those calls they are a bug
that shouldn't spread elsewhere.
- The functionality benefit of automatic directory creation is
questionable. It was probably only included in vo_jpeg because of
the option to automatically create multiple subdirectories (though
the utility of that is also questionable); vo_png does not have that.